System of control.



G. E. LORD SYSTEM OF CONTROL. APPLICATION FILED NOV. so, 19 0.

Patented De0.10,1912.

CHARLES E. LORD, OF MILWAUKEE, WISCONSIN.

SYSTEM OF CONTROL.

Specification of Letters Patent.

Patented Dec. 10,1912.

Application filed November 30, 1910. Serial No. 594,820.

T 0 all whom it may concern:

Be it known that I, CHARLES E. LORD, a citizen of the United States, residing at Milwaukee, in .the county of Milwaukee and- St-ate of WVisconsin, have invented certain new and useful Improvements in Systems of Control, of which the following is a full, clear, and exact specification.

This invention relates to systems of control of the separately actuated contact type in which the several controller contacts or switches are arranged to be operated successively and automatically. 7

- The object of my invention is to so construct and arrange the cont-roller contacts and their connections as to prevent a too rapid successive operation of the contacts thereby preventing a too rapid acceleration of the motor controlled thereby.

In carrying out my invention I obtain the proper time element between successively 01)- erated switches by means of a compressible -resistance device, preferably an automatically operated compressible carbon resistance element.

The various novel features of my mven- 'tion will be described in the specification and particularly set forth in the appended claims.

The invention is illustrated somewhat diagrammatically in the accompanying draw- The motor 10, here shown as having a shunt field 11, is connected to a source of supply 12 by a switch 13. In order to vary the speed of the motor, sections 1", T and r of resistance. are connected in series with said motor. These sections of resistance are adapted to be cut into and out of the m'otor circuit by automatically operated electromagnetic switches 1, 2, andB, the o crations of which are, controlled by solenoi s 14:, 15, and 16 respectively included in the energizing circuit or circuits 17. The energiz'at-ion of the solenoids 14, 15, and 16 is controlled by time element devices 18, 19, and 20. Each of these devices, considering the first device 18 particularly, includes a variable compressible resistance member 21 referably formed of a pile of carbon isks. The time element devices are adapted to be actuated by magnets 22, the energizingcoils 23 of which are in the motor circuit. a

To prevent a too rapid successive operation of the switches 1, 2, and 3 by al'sudden and sharp heavy compressive action of the devices 18,19, and 20, said devices are providedwith retarding-members or dash-pots 24. Thepressure on the variable compres- ,sible.resistance mediums is thereby applied nected in series. with their correspondingvariable resistance members.

When theline switch 13 is closed current is forced through conductor 25, bridging contact 26 of switch '3, conductor 27 to point 28. Here the current divides, part passing through energizing coil 28, sections 1*, W, and r of resistance, and motor 10 to ground G. The motor 10 is thereupon set in rotation and gradually increases its speed a predetermined amount. The other part of the current passes through variable resistance member 21, energizing coil 14 of switch No. 1, and conductor 29 to ground G. The current passing through the variable "compressible resistance member 21 is small due to theffact that the resistance of said carbon pile or resistance member is comparatively high when it is not compressed. But as the magnet 22 gradually elfects; the compression of the variable resistance medium 21 the current passing therethrough increases in value until it reaches a certain predeter;

mined strength which enables the coil 14 to actuate ancLcLose switch No. 1, cutting section r" of resistance out of the motor circuit and permitting the motor to take on an increment of speed. At this time the motor current passes from the source of supply through conductor 25, bridging contact 26, conductor 27, coil 23 of device 18, bridging contact 30 of'switch No. 1, actuating coil 23 of device 19, sections 7 and r of resistance, through motor 10 to ground G. The energizing circuit includes the same path as above mentioned until the point 31 is reached'where it divides and passes through the second variable resistance medium 32 of device 19, solenoid 15,-conductor 29 to ground G As the operating magnet 22 of device. 19 gradually efl'ectsthecompression of the carbon pile 32, current .will pass through the solenoid 15, increasing in value until it reaches a certain predetermined value, at which value it operates and closes switch No. 2, cutting out the second section r of resistance and permitting the motor 10 to take on another increment of speed. The motor current will now take a path through conductor 25', bridging contact 26, conductor 2?, coil 23 of device 18, bridging contact 30, coil 23 of device 19, bridging contact 34: of switch No. 2, coil23 of device 20, section 2" of resistance, motor '10 to ground G. The current used for actuating the switches 1, 2, and 3 will take exactly the same path to the point 35 where it will divide, passing through carbon pile 36 of device 20, solenoid l6, conductorQQ, to ground G. As

the carbon pile 36 is gradually compressed,=

the strength of the current passing therethrough will increase proportionately until it has reached a certain predetermined value when it will energize the solenoid l6 sufficiently to operate the switch No. 3, bringing its bridging contact 37 into engagement with its corresponding stationary contacts 38,39, and 40, and'breaking the connection between its bridging contact 26 and its stationary contacts ll and 42. At this point the third and last section r of resistance is'cut out of the motor circuit which now includes only 'the switch 13, conductor 25, conductor 43, bridging contact 37, motor l0 to ground Gr. Switch No. 3 is retained in this position by a holding coil 4% which receives its current through conductors 25 and 43, bridging contact 37, passing through a resistance 45, conductor 29 to ground G The resistance is inserted in the circuit for the purpose of cutting down the energizing current while the motoristin continuous operation. When switch l lo. 3 is operated and retained this runmngposr tlon it breaks certain circuit connections in eluding energizing magnets 22, solenoids 1ft, 15, and 16, thereby causing the switches No, l and No 2 to open. But switch No. 3 is held in its closed or running position by the holding coil 44%. When the line switch. 13

is opened, current willcease to pass through the holding coil 4L4. and switch No. 3 will be returned to its original starting position of which varies with change. of pressure and a solenoid in parallel with said element controlling the change in pressure.

2. An automatic circuit controller comprising a pluralityof electromagnetic switches, and time limit means controlling said switches and comprising an element or elements the resistance of which varies with change of pressure and means in parallel with said element or elements controlling the change in pressure.

3. An automatic circuit-controller comprising a plurality of switches, operating magnets for said switches, and compressible resistance means in circuit therewith for controlling the operation of said magnets.

4. An automatic circuit controller comprising a plurality of switches. operating means therefor, and compressible resistance means in circuit with said operating means for controlling the operation of said operating means.

5. An automatic circuit controller comprising a plurality of switches, and electrically controlled compressible resistance means for successively controlling said switches.

6. An automatic circuit controller comprising a plurality of electromagnetic switches, and electrically controlled compressible resistance means for successively controlling said switches.

-7. An automatic circuit controller comprising plurality of electromagnetic switches, and a plurality of electrically controlled compressible resistance devices for successively controlling said switches..-

8. An automatic circuit controller comprising a pluralit of electromagnetic -switches,,and electrically controlled compressible resistance devices in series with the magnet coils of: said sw1tches for successively controlnng the switches;

9. An automatic circuit controller comprising a plurality of electronic etic switches each having an operating e01 and compressible resistance devices in circuit electrically controlled compressible resist-- ance devices in series with said operating coil for effecting the operation of said switches.

12. An automatic circuit controller comprising a plurality of switches, and compressible resistance means controlled by cue of said switches for effecting the operatwn of another, said means including the resistance in one circuit and an electrical actuator in a branch circuit.

13. An automatic circuit controller'comprising a plurality of switches each having an operating coil, and a compressible re sistance device in series with the operating -coil of one of said switches for controlling said switch, said device including an electrical actuator in parallel with the resistance.

14. An automatic circuit contr0ller co mprising a plurality of switches each having an operating coil, and a compressibleresistance device in series with the eperating coil of one of said switches and controlled by another for effecting the operation of the former, said device including an electrical actuator in parallel with the resistance.

15. An automatic circuit controller comprising a plurality of switches, electromagnetic devices for actuating said switches, compressible resistance means in circuit with said actuating devices and for successively Copies of this patent may be obtained-tor controlling the actuating devices, and means controlled by the last of the series of switches for deenergizing others of the serles.

16. An automatic circuit controller com- 'sin -a plurality of switches, electromagqnc' evices for actuating said switches, a compressible resistance device in series with each of said devices comprising a resistance- 40 member, means controlling the pressure on said resistance members for increasing the current pa-ssingitherethrough, one of said switches controlling the com ressible device of the next succeeding swi'tc 17. The combination with an electric motor, of a plurality of resistances in circuit therewith, switches for successively shortcircuitingsaid resistances, compressible resistance means controlled by one of said switches for effecting the operation of the next succeeding switch, and means whereby the operation of the last of the series of switches. denergizes theintermediate switches. a

Milwaukee, Wis, Nov. 25, 1910. In testimony whereofl afiix my signature, in the presence of two witnesses.

" CHARLES E. LORD.

Witnesses CHAs. L. BYnoN, Ron. E. S'rom.

five cents each, by'afidressing the "Commissioner oi Patents. Washington, D. G. 

